Car trouble, want educated guesses.... (mechanic, year)

[headingtoDenver]

Originally Posted by greatblueheron

Thanks....I'm not car smart....it's a 6 cyl...engine light goes on and off.

I believe this is the first you have mentioned this. If, while driving, your check engine light blinks at times, this is a misfire which people have outlined what could be the cause.

[tickyul]

Stored-codes that have cycled-out of the system long enough so the CEL is off, they can be very useful.

[B2dathird]

Is the AIR filter good??

[dijkstra]

Originally Posted by greatblueheron

Thanks....I'm not car smart....it's a 6 cyl...engine light goes on and off.

It will have the codes stored as long as it does not cycle through all the check down procedures in the programming to delete them. If the light keeps coming on and going off, the codes will be in there and can be retrieved. It is probably going to be a misfire code for a particular cylinder P0301-P0306 or possible the random multiple misfire code P0300. If it is a particular cylinder code, take that spark plug out and inspect it. If it looks fine, it is probably a coil pack. If you have other codes, it could be something else. All of this is just speculation without knowing the codes.

[ddm2k]

Originally Posted by dijkstra

It will have the codes stored as long as it does not cycle through all the check down procedures in the programming to delete them. If the light keeps coming on and going off, the codes will be in there and can be retrieved. It is probably going to be a misfire code for a particular cylinder P0301-P0306 or possible the random multiple misfire code P0300. If it is a particular cylinder code, take that spark plug out and inspect it. If it looks fine, it is probably a coil pack. If you have other codes, it could be something else. All of this is just speculation without knowing the codes.

All very good information. If OP is not comfortable doing work alone, and doesn't have a trusted mechanic, it helps to explore your social circle in search of someone who can do this for you.

[greatblueheron]

Originally Posted by ddm2k

All very good information. If OP is not comfortable doing work alone, and doesn't have a trusted mechanic, it helps to explore your social circle in search of someone who can do this for you.

I regret saying this because everyone will ignore me now but I'm a not-car-smart lady.

Thanks for the suggestions all......I have some very good ideas to focus on...

[timfountain]

MAFs, o2 sensors and/or a dirty throttlebody would be my first port of call, after reading codes.... Could also be coilpacks.

[HJ99]

Start with basics, does the engine have good compression in all cylinders. Everybody immediately thinks electronics, but you first need to know the mechanical condition of the engine.



Saying all that, yea could well be bad injector or bad MAF. OR look for hidden air leaks in the hose/tube going from air filter box and MAF to the throttle body. A secret hidden little split in this tube or connectors at end of it, throwing off measurement of incoming air will throw off all kinds readings and drive you crazy diagnosing it. A bad injector or such should throw a code. This car is old enough it could be lot things. Though most should throw a code.

[cfenn006]

Originally Posted by greatblueheron

Nissan Murano, 2003, 126,000...nothing other than maintenance, been great car

-after starting car, runs rough in idle
-when pressing pedal and advancing, car increases in roughness, sputters...feels like it could cut off any moment
-has gotten progressively worse over several months. When it first appeared, service personnel claimed they could find nothing wrong.

Now I have a vehicle that seems is going to conk out somewhere along the road.

Just asking for speculations

What could it be?

Check:
Exhaust Leaks
PCV Valve
EGR Valve (Specifically if SES light is on)


Ignition Coil
Spark Plug Wires (Maybe came loose and is contact a manifold)
Spark Plugs


If the SES light is on take it to Auto Zone ORileys, ect for a scan.

[txtea]

It's been over 2 years since original post. I'm sure it's fixed by now